This invention relates to body structure of a mass transit vehicle and particularly to an arrangement including a fabricated frame over which are applied roof, floor and side cladding elements.
Conventionally mass transit vehicles and particularly city buses are manufactured from a welded steel frame defining a floor frame, side wall frame and roof bows which is then clad using sheet cladding material riveted, glued or otherwise fixed to the frame. Insulation material is inserted between the frame members inside the exterior cladding and outside of the interior cladding.
The exterior cladding is conventionally sheet aluminium, stainless steel or fiberglass and this structure is highly labour intensive requiring extensive cutting, forming and attachment of the various cladding components.
The roof structure is similarly conventionally manufactured from sheet aluminium or molded fiberglass skins which is applied over the roof bows and similarly riveted or glued in place.
The flooring is conventionally applied from individual panels which are arranged edge to edge across the floor frame and fastened to the floor frame by conventional fasteners. The floor panels are often fabricated from plywood but however composite materials are also sometimes used including flooring panels manufactured from fibre reinforced plastics material. One particular panel is manufactured from top and bottom sheets of a fibrous mat applied on top and bottom surfaces of a honeycomb material manufactured from phenolic resin impregnated paper with a thermosetting foam introduced into the honeycomb cores. The honeycomb panel is available from Westwind Composites Inc under the trade mark Weskor.
However the panels are formed, they are conventionally rectangular and arranged edge to edge and cut to shape and to size to complete the necessary flooring overlay.
It is also proposed to manufacture bus structures from fibre reinforced composite plastics material so that the side walls, roof structure and floor are each formed separately from such composite materials and are attached together to form the complete bus structure without the necessity for an additional frame supporting the structure.
Examples are shown in the following.
German Utility Model G88 07 208.8 of Gottlob Auwarter GmbH which shows a molded body structure.
U.S. Pat. No. 3,100,458 of Bristol Aeroplane Plastics Ltd. which shows a molded railway vehicle body molded around framing elements.
U.S. Pat. No. 5,797,646 of GEC Alsthom Transport which shows a vehicle body molded as a roof structure, floor structure with upturned sides and a series of side panels.
European application 864,483 of Fokker Special Products which shows a vehicle body molded again in four pieces defined by a floor structure, roof structure and two side panels.
U.S. Pat. No. 5,042,395 of Messerschmitt-Bolkow-Blohm GmbH which shows a rail car formed from joined molded elements defined by a floor panel, a roof panel and two side walls using special corner connectors.
U.S. Pat. No. 5,066,067 of Relco, Inc. discloses a bus structure formed by molded side walls and a molded roof structure together with a floor defined by two plywood sheets and a covering fibreglass layer.
In all of the above arrangements, therefore, the floor structure is intended to be a structural member by itself which attaches to the sidewalls and the roof to form an integral structural assembly.
In arrangements where the structure is provided by a separate frame, it is conventional merely to apply a flooring layer over the frame of sufficient strength to support passengers and other elements located on the floor while not contributing significantly to the structural strength of the bus body itself.
It is one object of the present invention, therefore, to provide an improved public transit vehicle.
According to a first aspect of the invention there is provided a public transit vehicle comprising:
a vehicle body having:
a roof,
two side walls each extending longitudinally of the vehicle including an upper side wall portion connecting to the roof and a row of windows underneath the upper portion,
a vehicle floor;
two rows of seats for seated passengers each along a respective one of the side walls at the windows and defining a central aisle therebetween for standing and moving passengers;
a bottom frame including a plurality of rails supporting the floor;
two side frames each including a plurality of upstanding posts and a plurality of longitudinally extending members interconnecting the posts;
the vehicle floor including a flooring sheet spanning between the side walls and molded from a composite panel having an upper skin, a lower skin and an intervening core material layer, the panel containing a cured resin material and the upper and lower skins including reinforcing fibers;
the panel being substantially planar thus defining a floor plane and such that the upper skin forms a substantially flat floor surface;
the upper and lower skins being continuous over the extent of the panel so as, at least over a part of a length of the floor, to span between the side walls;
the panel having at least one first portion thereof at which the core material layer is of different thickness than at other portions wherein the upper skin is flat and the lower skin is shaped to follow the thickness of the core material layer;
and the panel having at least one second portion thereof at which the upper and lower skins are shaped out of the floor plane to form a raised or lowered section of the floor surface.
Preferably the core material layer includes at least parts thereof which are formed from a sheet of a honeycomb foam filled material.
Preferably the floor includes a front lower deck extending from a position adjacent a front wall to a transverse step and a rear upper deck extending from the transverse step to a rear wall with the transverse step between the decks, the front deck being formed from a single flooring sheet spanning substantially wholly from the position adjacent the front wall to the transverse step and between the side walls and the rear deck being formed from a single flooring sheet spanning substantially wholly from the rear wall to the transverse step and between the side walls.
Preferably the front deck includes a downwardly inclined second portion at a forward end thereof.
Preferably the rear deck includes an upwardly inclined second portion adjacent the rear wall.
Preferably the panel is planar at the side edges thereof.
Preferably the bottom frame includes two longitudinal side rails and a plurality of transverse rails and wherein the panel is attached to the rails of the bottom frame by adhesive.
Preferably the side walls each include an interior cladding portion which extends downwardly and inwardly to the floor panel and includes a bottom edge spaced inwardly from and covering the respective side edge of the floor panel.
Preferably the floor panel includes a floor covering bonded to and carried by the upper skin and wherein the floor covering engages over the bottom edge of the cladding portion.
Preferably the panel includes a first portion where the core material layer is of reduced thickness at an axle of the vehicle such that the floor defines a bottom recess into which the axle can project when raised in a suspension movement.
Preferably the panel includes a first portion wherein the core material is of increased thickness at a rear door of the vehicle.
According to a second aspect of the invention there is provided a public transit vehicle comprising:
a vehicle body having:
a roof,
two side walls each extending longitudinally of the vehicle including an upper side wall portion connecting to the roof and a row of windows underneath the upper portion,
a vehicle floor;
two rows of seats for seated passengers each along a respective one of the side walls at the windows and defining a central aisle therebetween for standing and moving passengers;
two side frames each including a plurality of upstanding posts and a plurality of longitudinally extending members interconnecting the posts;
a roof frame including a plurality of transverse beams spanning the roof;
each side wall including an exterior cladding structure attached to the side wall frame and carried thereby;
a roof sheet extending over the roof frame and supported thereby;
the roof sheet being molded from a composite panel having an upper skin, a lower skin and an intervening core material layer, the panel containing a cured resin material and the upper and lower skins including reinforcing fibers;
the upper and lower skins being continuous over the extent of the panel.
Preferably the panel is arched in transverse cross-section.
Preferably the exterior cladding structure of each side wall includes a curved coping panel which extends from the side wall upwardly and inwardly to the roof panel.
Preferably the coping panel includes a joint portion extending longitudinally of the panel at its edge adjacent the roof panel, the roof panel including an overlapping flange member extending longitudinally thereof at and overlapping with the joint portion of the coping panel.
Preferably the joint portion carries a sealing bead for sealing against the flange portion while allowing outward expansion movement of the flange portion of the roof panel relative to the joint portion of the coping panel.
Preferably the joint portion is integral with the coping panel and the flange portion is integral with the roof panel and forms an extension of the upper and lower skins thereof.
According to a third aspect of the invention there is provided a public transit vehicle comprising:
a vehicle body having:
a roof having a roof panel,
two side walls each extending longitudinally of the vehicle including an upper side wall portion connecting to the roof and a row of windows underneath the upper portion,
a vehicle floor;
two rows of seats for seated passengers each along a respective one of the side walls at the windows and defining a central aisle therebetween for standing and moving passengers;
two side frames each including a plurality of upstanding posts and a plurality of longitudinally extending members interconnecting the posts;
each side wall including an exterior cladding structure attached to the side wall frame and carried thereby;
the exterior cladding structure of each side wall including a curved coping panel which extends from the a top edge of the windows of the side wall upwardly and inwardly to the roof panel
the exterior cladding structure of each side wall including a side wall panel which extends from a bottom edge of the windows of the side wall downwardly;
each of the coping panel and the side wall panel comprising a molded sheet defining an outer surface facing outwardly of the side wall and an inner surface, the inner surface carrying a layer of insulation material attached thereto and carried thereby.
Preferably each of the coping panel and the side wall panel is attached to the side wall frame by adhesive/sealant material.
Preferably the exterior cladding structure of each side wall includes a drip rail having a flange portion engaged underneath a bottom edge of the coping panel.
Preferably the coping panel includes a joint portion extending longitudinally of the panel at its edge adjacent the roof panel, the roof panel including an overlapping flange member extending longitudinally thereof at and overlapping with the joint portion of the coping panel.
Preferably the exterior cladding structure of each side wall includes a plurality of flexible impact panels arranged end to end longitudinally of a bottom edge of the side wall panel and attached thereto.
Preferably the flexible impact panels cover a layer of insulation attached to and carried by the side wall frame.